The present invention relates to a device for recording image information to a medium or a device for playing back image information from a medium.
Examples of systems for playing back image information recorded on media include VCRs, which have been in use for a long time, as well as video CDs, which use an optical disk with a 12 cm diameter as the recording medium. Recently, DVDs, which use an optical disk with the same diameter but with approximately seven times the recording capacity, have emerged.
In DVD playback devices, numbers are assigned to: recorded programs (in DVDs, these are called “titles” and will be referred to as such below); the plurality of scenes contained in a title (in DVDs, these are called “chapters” and will be referred to as such below); and frames, which are the basic units of the images. Cueing, where a desired image is displayed at the beginning, is accomplished by entering a title number, a chapter number, and a frame number for a desired image, determining a playback position on the disk, and playing back images beginning with this position (e.g., see Japanese laid-open patent publication number Hei 7-312737).
Also, when multiple sets of supplementary information (e.g., “multi-angle” information containing multiple images from different perspectives, separate left and right channels of audio, and different languages such as Japanese and English) are recorded simultaneously with the images, and playback conditions are selected by selecting which supplementary information to use. The selection of playback conditions is performed by switching between screens for each set of information and checking the contents of each. Supplementary information can also be recorded beforehand on the disk as a menu of playback conditions (e.g., see Japanese laid-open patent publication number 8-251531).
The conventional technologies described above are effective in cases, such as with karaoke disks, where the producer of a disk deliberately assigns numbers (e.g., numbers are assigned according to the sequence of songs) and the documentation or the like for the disk indicates the meaning associated with the numbers. However, this does not provide effective means for selecting if a user attempts to access images without the documentation. This makes accessing and searching an arbitrary position on a disk difficult. Also, it is not possible to look through the multiple sets of supplementary information all at once, thus making selection time consuming. Furthermore, if a menu for the information is recorded beforehand, the method used to display and select the information will vary according to the intentions of the program producers. This is inconvenient since each disk will involve a different method.
Also, knowing the overall content of a stream (where a stream is the information for a series of connected scenes) is difficult.
There is a need to overcome the problems of the conventional technology described above and to provide a novel information playback device that allows easy searching of information through unified operations and that allows the contents of all or at least part of a stream to be perceived and selected from a playback screen.